2 cases : 1) IF FREE... As far as I saw... many web directories only get PR only on the main index. The rest are N/A. So it is like this.. Google will reward you with the correct PageRank, but for directories... only the index is getting PR so you can't sell a lot of lins and make profit upon Google PageRank Trademark from now on. 2) IF PAID... your web directory is screwed...or it will be untill the next PR like other major web directories did... Am I right ?!
you have a lot of examples...what happened to aviva,romow,kwikgoblin,sevenseek,topdirectories.info,etc... The most promoted got the most fucked ! OR...you will have PR8 on you index... and PR N/A on your categories... and I don't believe that somebody will actually buy links... maybe on your index yes. I might be wrong...but this is how I see it.
That is just a small portion of paid directories, no one has proof that the reason they are penalized is because it is a paid directory, they might have had a listing in the directory that google didn't like, or possibly because jeff started the Google Killer, i and yes once again you are wrong, and maybe doing some research and before you see it again. As hitler said "The great masses of the people... will more easily fall victims to a big lie than to a small one." Think about that, or in your case An empty stomach is not a good political adviser. as Einsten said.